The scientists at Cold Spring Harbor Laboratory have been actively incorporating next generations sequencing into a broad range of NIH supported research projects since we obtained our first next generation instrument. Our current instruments are primarily Illumina HiSeq 2000s. These instruments were introduced in 2010 and have been replaced on the market by the Illumina HiSeq 2500. We currently have no HiSeq 2500s at CSHL. The HiSeq 2500 provides higher output, longer quality read length and a lower cost per base for data than does the HiSeq 2000. In addition, new chemistry that has been announced by Illumina will provide even greater cost efficiency and faster run times than are currently available on the HiSeq 2500. This new chemistry will only be available for the newer HiSeq 2500 instruments, not our older models. We are requesting funds to purchase an Illumina HiSeq 2500 so that we can continue providing state of the art, cost effective next generation sequencing to the CSHL community of NIH funded researchers.